use other calendar than Gregorian

hi, thank you for your hardworking
I want to use Persian Calendar and Persian date instead of Gregorian date. In GxCommon there is method

private static void SetDateTime(GXDLMSSettings settings, GXByteBuffer buff, object value)
{
}

that change Gregorian date to 12 byte Dlms format. I want to know if there is simple workaround to use Persian Date in this function and other related parts.
I want to update my dlms code according your updates and don't want to change this code personally.
thank you in advance.